// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/renderer/pepper/v8_var_converter.h"

#include <stddef.h>
#include <stdint.h>

#include <cmath>
#include <memory>

#include "base/logging.h"
#include "base/memory/ref_counted.h"
#include "base/message_loop/message_loop.h"
#include "base/run_loop.h"
#include "base/synchronization/waitable_event.h"
#include "base/values.h"
#include "content/renderer/pepper/resource_converter.h"
#include "ppapi/c/pp_bool.h"
#include "ppapi/c/pp_var.h"
#include "ppapi/shared_impl/array_var.h"
#include "ppapi/shared_impl/dictionary_var.h"
#include "ppapi/shared_impl/ppapi_globals.h"
#include "ppapi/shared_impl/proxy_lock.h"
#include "ppapi/shared_impl/scoped_pp_var.h"
#include "ppapi/shared_impl/test_globals.h"
#include "ppapi/shared_impl/test_utils.h"
#include "ppapi/shared_impl/var.h"
#include "ppapi/shared_impl/var_tracker.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "v8/include/v8.h"

using ppapi::ArrayBufferVar;
using ppapi::ArrayVar;
using ppapi::DictionaryVar;
using ppapi::PpapiGlobals;
using ppapi::ProxyLock;
using ppapi::ScopedPPVar;
using ppapi::StringVar;
using ppapi::TestEqual;
using ppapi::TestGlobals;
using ppapi::VarTracker;

namespace content {

namespace {

    void FromV8ValueComplete(const ScopedPPVar& scoped_var,
        bool success)
    {
        NOTREACHED();
    }

    class MockResourceConverter : public content::ResourceConverter {
    public:
        ~MockResourceConverter() override { }
        void Reset() override { }
        bool NeedsFlush() override { return false; }
        void Flush(const base::Callback<void(bool)>& callback) override
        {
            NOTREACHED();
        }
        bool FromV8Value(v8::Local<v8::Object> val,
            v8::Local<v8::Context> context,
            PP_Var* result,
            bool* was_resource) override
        {
            *was_resource = false;
            return true;
        }
        bool ToV8Value(const PP_Var& var,
            v8::Local<v8::Context> context,
            v8::Local<v8::Value>* result) override
        {
            return false;
        }
    };

    // Maps PP_Var IDs to the V8 value handle they correspond to.
    typedef base::hash_map<int64_t, v8::Local<v8::Value>> VarHandleMap;

    bool Equals(const PP_Var& var,
        v8::Local<v8::Value> val,
        VarHandleMap* visited_ids)
    {
        if (ppapi::VarTracker::IsVarTypeRefcounted(var.type)) {
            VarHandleMap::iterator it = visited_ids->find(var.value.as_id);
            if (it != visited_ids->end())
                return it->second == val;
            (*visited_ids)[var.value.as_id] = val;
        }

        v8::Isolate* isolate = v8::Isolate::GetCurrent();
        if (val->IsUndefined()) {
            return var.type == PP_VARTYPE_UNDEFINED;
        } else if (val->IsNull()) {
            return var.type == PP_VARTYPE_NULL;
        } else if (val->IsBoolean() || val->IsBooleanObject()) {
            return var.type == PP_VARTYPE_BOOL && PP_FromBool(val->ToBoolean(isolate)->Value()) == var.value.as_bool;
        } else if (val->IsInt32()) {
            return var.type == PP_VARTYPE_INT32 && val->ToInt32(isolate)->Value() == var.value.as_int;
        } else if (val->IsNumber() || val->IsNumberObject()) {
            return var.type == PP_VARTYPE_DOUBLE && fabs(val->ToNumber(isolate)->Value() - var.value.as_double) <= 1.0e-4;
        } else if (val->IsString() || val->IsStringObject()) {
            if (var.type != PP_VARTYPE_STRING)
                return false;
            StringVar* string_var = StringVar::FromPPVar(var);
            DCHECK(string_var);
            v8::String::Utf8Value utf8(val);
            return std::string(*utf8, utf8.length()) == string_var->value();
        } else if (val->IsArray()) {
            if (var.type != PP_VARTYPE_ARRAY)
                return false;
            ArrayVar* array_var = ArrayVar::FromPPVar(var);
            DCHECK(array_var);
            v8::Local<v8::Array> v8_array = val.As<v8::Array>();
            if (v8_array->Length() != array_var->elements().size())
                return false;
            for (uint32_t i = 0; i < v8_array->Length(); ++i) {
                v8::Local<v8::Value> child_v8 = v8_array->Get(i);
                if (!Equals(array_var->elements()[i].get(), child_v8, visited_ids))
                    return false;
            }
            return true;
        } else if (val->IsObject()) {
            if (var.type == PP_VARTYPE_ARRAY_BUFFER) {
                // TODO(raymes): Implement this when we have tests for array buffers.
                NOTIMPLEMENTED();
                return false;
            } else {
                v8::Local<v8::Object> v8_object = val.As<v8::Object>();
                if (var.type != PP_VARTYPE_DICTIONARY)
                    return false;
                DictionaryVar* dict_var = DictionaryVar::FromPPVar(var);
                DCHECK(dict_var);
                v8::Local<v8::Array> property_names(v8_object->GetOwnPropertyNames());
                if (property_names->Length() != dict_var->key_value_map().size())
                    return false;
                for (uint32_t i = 0; i < property_names->Length(); ++i) {
                    v8::Local<v8::Value> key(property_names->Get(i));

                    if (!key->IsString() && !key->IsNumber())
                        return false;
                    v8::Local<v8::Value> child_v8 = v8_object->Get(key);

                    v8::String::Utf8Value name_utf8(key);
                    ScopedPPVar release_key(ScopedPPVar::PassRef(),
                        StringVar::StringToPPVar(std::string(
                            *name_utf8, name_utf8.length())));
                    if (!dict_var->HasKey(release_key.get()))
                        return false;
                    ScopedPPVar release_value(ScopedPPVar::PassRef(),
                        dict_var->Get(release_key.get()));
                    if (!Equals(release_value.get(), child_v8, visited_ids))
                        return false;
                }
                return true;
            }
        }
        return false;
    }

    bool Equals(const PP_Var& var, v8::Local<v8::Value> val)
    {
        VarHandleMap var_handle_map;
        return Equals(var, val, &var_handle_map);
    }

    class V8VarConverterTest : public testing::Test {
    public:
        V8VarConverterTest()
            : isolate_(v8::Isolate::GetCurrent())
        {
            PP_Instance dummy = 1234;
            converter_.reset(new V8VarConverter(
                dummy, std::unique_ptr<ResourceConverter>(new MockResourceConverter)));
        }
        ~V8VarConverterTest() override { }

        // testing::Test implementation.
        void SetUp() override
        {
            ProxyLock::Acquire();
            v8::HandleScope handle_scope(isolate_);
            v8::Local<v8::ObjectTemplate> global = v8::ObjectTemplate::New(isolate_);
            context_.Reset(isolate_, v8::Context::New(isolate_, NULL, global));
        }
        void TearDown() override
        {
            context_.Reset();
            ASSERT_TRUE(PpapiGlobals::Get()->GetVarTracker()->GetLiveVars().empty());
            ProxyLock::Release();
        }

    protected:
        bool FromV8ValueSync(v8::Local<v8::Value> val,
            v8::Local<v8::Context> context,
            PP_Var* result)
        {
            V8VarConverter::VarResult conversion_result = converter_->FromV8Value(val,
                context,
                base::Bind(&FromV8ValueComplete));
            DCHECK(conversion_result.completed_synchronously);
            if (conversion_result.success)
                *result = conversion_result.var.Release();

            return conversion_result.success;
        }

        bool RoundTrip(const PP_Var& var, PP_Var* result)
        {
            v8::HandleScope handle_scope(isolate_);
            v8::Local<v8::Context> context = v8::Local<v8::Context>::New(isolate_, context_);
            v8::Context::Scope context_scope(context);
            v8::Local<v8::Value> v8_result;
            if (!converter_->ToV8Value(var, context, &v8_result))
                return false;
            if (!Equals(var, v8_result))
                return false;
            if (!FromV8ValueSync(v8_result, context, result))
                return false;
            return true;
        }

        // Assumes a ref for var.
        bool RoundTripAndCompare(const PP_Var& var)
        {
            ScopedPPVar expected(ScopedPPVar::PassRef(), var);
            PP_Var actual_var;
            if (!RoundTrip(expected.get(), &actual_var))
                return false;
            ScopedPPVar actual(ScopedPPVar::PassRef(), actual_var);
            return TestEqual(expected.get(), actual.get(), false);
        }

        v8::Isolate* isolate_;

        // Context for the JavaScript in the test.
        v8::Persistent<v8::Context> context_;

        std::unique_ptr<V8VarConverter> converter_;

    private:
        base::MessageLoop message_loop_; // Required to receive callbacks.

        TestGlobals globals_;
    };

} // namespace

TEST_F(V8VarConverterTest, SimpleRoundTripTest)
{
    EXPECT_TRUE(RoundTripAndCompare(PP_MakeUndefined()));
    EXPECT_TRUE(RoundTripAndCompare(PP_MakeNull()));
    EXPECT_TRUE(RoundTripAndCompare(PP_MakeInt32(100)));
    EXPECT_TRUE(RoundTripAndCompare(PP_MakeBool(PP_TRUE)));
    EXPECT_TRUE(RoundTripAndCompare(PP_MakeDouble(53.75)));
}

TEST_F(V8VarConverterTest, StringRoundTripTest)
{
    EXPECT_TRUE(RoundTripAndCompare(StringVar::StringToPPVar("")));
    EXPECT_TRUE(RoundTripAndCompare(StringVar::StringToPPVar("hello world!")));
}

TEST_F(V8VarConverterTest, ArrayBufferRoundTripTest)
{
    // TODO(raymes): Testing this here requires spinning up some of WebKit.
    // Work out how to do this.
}

TEST_F(V8VarConverterTest, DictionaryArrayRoundTripTest)
{
    // Empty array.
    scoped_refptr<ArrayVar> array(new ArrayVar);
    ScopedPPVar release_array(ScopedPPVar::PassRef(), array->GetPPVar());
    EXPECT_TRUE(RoundTripAndCompare(array->GetPPVar()));

    size_t index = 0;

    // Array with primitives.
    array->Set(index++, PP_MakeUndefined());
    array->Set(index++, PP_MakeNull());
    array->Set(index++, PP_MakeInt32(100));
    array->Set(index++, PP_MakeBool(PP_FALSE));
    array->Set(index++, PP_MakeDouble(0.123));
    EXPECT_TRUE(RoundTripAndCompare(array->GetPPVar()));

    // Array with 2 references to the same string.
    ScopedPPVar release_string(ScopedPPVar::PassRef(),
        StringVar::StringToPPVar("abc"));
    array->Set(index++, release_string.get());
    array->Set(index++, release_string.get());
    EXPECT_TRUE(RoundTripAndCompare(array->GetPPVar()));

    // Array with nested array that references the same string.
    scoped_refptr<ArrayVar> array2(new ArrayVar);
    ScopedPPVar release_array2(ScopedPPVar::PassRef(), array2->GetPPVar());
    array2->Set(0, release_string.get());
    array->Set(index++, release_array2.get());
    EXPECT_TRUE(RoundTripAndCompare(array->GetPPVar()));

    // Empty dictionary.
    scoped_refptr<DictionaryVar> dictionary(new DictionaryVar);
    ScopedPPVar release_dictionary(ScopedPPVar::PassRef(),
        dictionary->GetPPVar());
    EXPECT_TRUE(RoundTripAndCompare(dictionary->GetPPVar()));

    // Dictionary with primitives.
    dictionary->SetWithStringKey("1", PP_MakeUndefined());
    dictionary->SetWithStringKey("2", PP_MakeNull());
    dictionary->SetWithStringKey("3", PP_MakeInt32(-100));
    dictionary->SetWithStringKey("4", PP_MakeBool(PP_TRUE));
    dictionary->SetWithStringKey("5", PP_MakeDouble(-103.52));
    EXPECT_TRUE(RoundTripAndCompare(dictionary->GetPPVar()));

    // Dictionary with 2 references to the same string.
    dictionary->SetWithStringKey("6", release_string.get());
    dictionary->SetWithStringKey("7", release_string.get());
    EXPECT_TRUE(RoundTripAndCompare(dictionary->GetPPVar()));

    // Dictionary with nested dictionary that references the same string.
    scoped_refptr<DictionaryVar> dictionary2(new DictionaryVar);
    ScopedPPVar release_dictionary2(ScopedPPVar::PassRef(),
        dictionary2->GetPPVar());
    dictionary2->SetWithStringKey("abc", release_string.get());
    dictionary->SetWithStringKey("8", release_dictionary2.get());
    EXPECT_TRUE(RoundTripAndCompare(dictionary->GetPPVar()));

    // Array with dictionary.
    array->Set(index++, release_dictionary.get());
    EXPECT_TRUE(RoundTripAndCompare(array->GetPPVar()));

    // Array with dictionary with array.
    array2->Set(0, PP_MakeInt32(100));
    dictionary->SetWithStringKey("9", release_array2.get());
    EXPECT_TRUE(RoundTripAndCompare(array->GetPPVar()));
}

TEST_F(V8VarConverterTest, Cycles)
{
    // Check that cycles aren't converted.
    v8::HandleScope handle_scope(isolate_);
    v8::Local<v8::Context> context = v8::Local<v8::Context>::New(isolate_, context_);
    v8::Context::Scope context_scope(context);

    // Var->V8 conversion.
    {
        scoped_refptr<DictionaryVar> dictionary(new DictionaryVar);
        ScopedPPVar release_dictionary(ScopedPPVar::PassRef(),
            dictionary->GetPPVar());
        scoped_refptr<ArrayVar> array(new ArrayVar);
        ScopedPPVar release_array(ScopedPPVar::PassRef(), array->GetPPVar());

        dictionary->SetWithStringKey("1", release_array.get());
        array->Set(0, release_dictionary.get());

        v8::Local<v8::Value> v8_result;

        // Array <-> dictionary cycle.
        dictionary->SetWithStringKey("1", release_array.get());
        ASSERT_FALSE(
            converter_->ToV8Value(release_dictionary.get(), context, &v8_result));
        // Break the cycle.
        // TODO(raymes): We need some better machinery for releasing vars with
        // cycles. Remove the code below once we have that.
        dictionary->DeleteWithStringKey("1");

        // Array with self reference.
        array->Set(0, release_array.get());
        ASSERT_FALSE(
            converter_->ToV8Value(release_array.get(), context, &v8_result));
        // Break the self reference.
        array->Set(0, PP_MakeUndefined());
    }

    // V8->Var conversion.
    {
        v8::Local<v8::Object> object = v8::Object::New(isolate_);
        v8::Local<v8::Array> array = v8::Array::New(isolate_);

        PP_Var var_result;

        // Array <-> dictionary cycle.
        std::string key = "1";
        object->Set(
            v8::String::NewFromUtf8(
                isolate_, key.c_str(), v8::String::kNormalString, key.length()),
            array);
        array->Set(0, object);

        ASSERT_FALSE(FromV8ValueSync(object, context, &var_result));

        // Array with self reference.
        array->Set(0, array);
        ASSERT_FALSE(FromV8ValueSync(array, context, &var_result));
    }
}

TEST_F(V8VarConverterTest, StrangeDictionaryKeyTest)
{
    {
        // Test keys with '.'.
        scoped_refptr<DictionaryVar> dictionary(new DictionaryVar);
        dictionary->SetWithStringKey(".", PP_MakeUndefined());
        dictionary->SetWithStringKey("x.y", PP_MakeUndefined());
        EXPECT_TRUE(RoundTripAndCompare(dictionary->GetPPVar()));
    }

    {
        // Test non-string key types. They should be cast to strings.
        v8::HandleScope handle_scope(isolate_);
        v8::Local<v8::Context> context = v8::Local<v8::Context>::New(isolate_, context_);
        v8::Context::Scope context_scope(context);
        v8::MicrotasksScope microtasks(
            isolate_, v8::MicrotasksScope::kDoNotRunMicrotasks);

        const char* source = "(function() {"
                             "return {"
                             "1: 'foo',"
                             "'2': 'bar',"
                             "true: 'baz',"
                             "false: 'qux',"
                             "null: 'quux',"
                             "undefined: 'oops'"
                             "};"
                             "})();";

        v8::Local<v8::Script> script(
            v8::Script::Compile(v8::String::NewFromUtf8(isolate_, source)));
        v8::Local<v8::Object> object = script->Run().As<v8::Object>();
        ASSERT_FALSE(object.IsEmpty());

        PP_Var actual;
        ASSERT_TRUE(FromV8ValueSync(
            object, v8::Local<v8::Context>::New(isolate_, context_), &actual));
        ScopedPPVar release_actual(ScopedPPVar::PassRef(), actual);

        scoped_refptr<DictionaryVar> expected(new DictionaryVar);
        ScopedPPVar foo(ScopedPPVar::PassRef(), StringVar::StringToPPVar("foo"));
        expected->SetWithStringKey("1", foo.get());
        ScopedPPVar bar(ScopedPPVar::PassRef(), StringVar::StringToPPVar("bar"));
        expected->SetWithStringKey("2", bar.get());
        ScopedPPVar baz(ScopedPPVar::PassRef(), StringVar::StringToPPVar("baz"));
        expected->SetWithStringKey("true", baz.get());
        ScopedPPVar qux(ScopedPPVar::PassRef(), StringVar::StringToPPVar("qux"));
        expected->SetWithStringKey("false", qux.get());
        ScopedPPVar quux(ScopedPPVar::PassRef(), StringVar::StringToPPVar("quux"));
        expected->SetWithStringKey("null", quux.get());
        ScopedPPVar oops(ScopedPPVar::PassRef(), StringVar::StringToPPVar("oops"));
        expected->SetWithStringKey("undefined", oops.get());
        ScopedPPVar release_expected(ScopedPPVar::PassRef(), expected->GetPPVar());

        ASSERT_TRUE(TestEqual(release_expected.get(), release_actual.get(), true));
    }
}

} // namespace content
